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1 Introduction With the proliferation of portable computing platforms and small wireless devices, ad hoc wireless networks have received more and more attention as a means of data communication among […], Power-saving is a critical issue for all kinds of portable devices. The power-saving mode of IEEE 802.11 is designed for a single-hop (or fully connected) ad hoc network and is not applicable for multi-hop ad hoc networks. In this paper, we propose an asynchronous power-saving protocol for mobile ad hoc networks (MANETs) with unpredictable mobility and multi-hop communication. Neighbors that wish to communicate estimate the relative phase difference between their sleep/awake cycles. A station uses this phase information for transmitting the pending traffic. Stations can also increase their awake period for transmitting the data and to reduce latency for delay sensitive flows. Simulation studies indicate that the proposed asynchronous protocol is quite effective under various traffic characteristics and loads; energy saving can be as high as 70%, while the packet delivery ratio is comparable to networks without power management. Key words: 802.11, ad-hoc networks, clock synchronization, scalability

This paper presents a new scheme of dynamic state estimation, utilizing a statistical approach called the M-Estimation to resolve the filtering problem robustly. In the prediction step, realistic treatment of system dynamics based on nodal analysis produces an efficient state prediction method. The proposed Robust Realistic Dynamic State Estimation (RRDSE) has been tested on 5-bus, 14-bus, and 30-bus test systems and the results are presented. The error analysis presented reveals the superiority of the proposed RRDSE particularly when the system measurements are under bad-data condition. Key words: Dynamic State Estimation, Kalman Filter, Robust Filtering, State Prediction, Power Systems, Dynamic Modeling.

The Main Central Thrust Zone (MCTZ) in the Alaknanda valley, NW Himalaya, affected the Lesser Himalayan Crystalline Sequence and has a gradual transition to the structurally overlying Higher Himalayan Crystalline Sequence (HHCS). This boundary is defined on the basis of the following petrographic features in pelitic rocks at the base of the HHCS: (i) first appearance of microscopic needles of kyanite upon moving up-section along the transect; (ii) garnet porphyroblasts with random inclusion pattern and non-rotational growth history, which contrast with the garnet porphyroblasts in MCTZ rocks with spiral inclusion trails; and (iii) chemically homogeneous garnet porphyroblasts as opposed to the growth-zoned garnets in MCTZ rocks. Pseudosection modelling and garnet isopleth thermobarometry of pelitic rocks yield peak metamorphic conditions of 6.3-7.5 kbar and 550-582°C in the MCTZ, and 8.0-10.0 kbar and 610-650°C in the basal part of the HHCS. The results indicate continuity in the P-T field gradient across the contact between the MCTZ and HHCS. The MCTZ shows an inverted metamorphic sequence from biotite to garnet zones. Metamorphism in the basal part of the HHCS is in the kyanite zone, which is continuous with the inverted metamorphic sequence. Both P and T increase up-section, peak in the lower HHCS and then decrease higher up in the HHCS unit. The observations are consistent with predictions of a recently proposed thermomechanical model in which temperature in the shear zone rises due to viscous heating and pressure rises as a result of weakening of the rocks. Keywords Inverted metamorphism * Pseudosection * Main central thrust zone * Garhwal Himalaya, Introduction The Main Central Thrust Zone (MCTZ) has long been recognised as one of the major terrane boundary shear zones of the Himalayan orogen that accommodated a significant amount of [...]